Table 1.
Group characteristicsa
| Variable | Total (n = 113) | EOAD (n = 60) | LOAD (n = 53) | P-value | Effect sizeb |
|---|---|---|---|---|---|
| Age at PET scan (years), mean (SD) | 65.5 (9.3) | 58.1 (3.9) | 73.9 (5.9) | <0.001 | 3.20 |
| Female sex, % (n) | 52% (59) | 58% (35) | 45% (24) | 0.17 | 0.13 |
| Race and ethnicity, % (n) | 0.16 | 0.24 | |||
| Asian or Pacific Islander | 4% (4) | 3% (2) | 4% (2) | ||
| Black or African American | 1% (1) | 2% (1) | 0 | ||
| Hispanic or Latino | 2% (2) | 3% (2) | 0 | ||
| White | 90% (102) | 85% (51) | 96% (51) | ||
| Declined to state | 4% (4) | 7% (4) | 0 | ||
| Education (years), mean (SD) | 16.8 (2.7) | 16.7 (3.0) | 16.9 (2.4) | 0.66 | 0.08 |
| Clinical diagnosis, % (n) | 0.15 | 0.22 | |||
| Mild cognitive impairment | 18% (20) | 12% (7) | 25% (13) | ||
| Alzheimer’s disease dementia | 45% (51) | 43% (26) | 47% (25) | ||
| Posterior cortical atrophy | 18% (20) | 23% (14) | 11% (6) | ||
| Logopenic variant primary progressive aphasia | 19% (22) | 22% (13) | 17% (9) | ||
| Amnestic presentation, % (n) | 56% (63) | 47% (28) | 66% (35) | 0.04 | 0.19 |
| ApoE4 ε4 allele, % (n) | 0.88 | 0.05 | |||
| None | 43% (40) | 45% (23) | 41% (17) | ||
| Heterozygous | 43% (40) | 41% (21) | 46% (19) | ||
| Homozygous | 13% (12) | 14% (7) | 12% (5) | ||
| PIB-PET Centiloid, mean (SD) | 92 (34) | 98 (27) | 85 (39) | 0.03 | 0.41 |
| FTP-PET temporal metaROI SUVR, mean (SD) | 2.0 (0.5) | 2.2 (0.5) | 1.9 (0.5) | <0.001 | 0.66 |
| MMSE, mean (SD) | 22.0 (5.7) | 20.9 (6.2) | 23.3 (4.8) | 0.03 | 0.42 |
| CDR ≤ 0.5, % (n) | 58% (66) | 53% (32) | 64% (34) | 0.24 | 0.11 |
| CDR Sum of Boxes, mean (SD) | 3.9 (2.1) | 4.0 (2.1) | 3.8 (2.2) | 0.51 | 0.12 |
| CD ≤ 0.5 in lvPPA/PCA, % (n) | 62% (26) | 67% (18) | 53% (8) | 0.39 | 0.13 |
| Z-score MMSECDRSum, mean (SD)c,d | 0.0 (1.8) | 0.2 (1.9) | −0.3 (1.7) | 0.11 | 0.30 |
| Episodic memory, W-score mean (SD)d | 2.6 (1.3) | 2.8 (1.4) | 2.4 (1.2) | 0.14 | 0.28 |
| Semantic memory, W-score mean (SD)d | 2.0 (1.9) | 2.0 (1.8) | 2.1 (2.1) | 0.78 | 0.05 |
| Language, W-score mean (SD)d | 1.9 (2.3) | 2.4 (2.3) | 1.4 (2.2) | 0.01 | 0.47 |
| Executive function, W-score mean (SD)d | 1.9 (1.2) | 2.3 (1.1) | 1.4 (1.1) | <0.001 | 0.78 |
| Visuospatial, W-score mean (SD)d | 2.5 (3.6) | 3.7 (3.9) | 1.2 (2.8) | <0.001 | 0.75 |
Bold font indicates significant differences between EOAD and LOAD groups.
a
Pearson χ2 and two-tailed t-tests were used to assess baseline group differences.
b
Effect size was measured using Cramér's V and Cohen’s d.
c
Mean of the Z-score of the MMSE and CDR Sum of Boxes.
d
Higher scores indicate greater impairment.